Sensitivity of Selected Vegetable and Weed Seedlings to Ultraviolet-B Radiation

Relative sensitivity of selected vegetable and weed seedlings to ultraviolet-B (UV-B) radiation (280–320 nm) was investigated. Seedlings were grown for 4 weeks in a greenhouse, in chambers equipped with UV-B-emitting fluorescent tubes and Mylar (control) and cellulose acetate (UV-B) filters. UV-B radiation reduced seedling height, leaf area, and leaf fresh weight in tomato (Lycopersicon esculentum `Cour Di Bue'), broccoli (Brassica oleracea var. Italica `Purple Sprouting'), cabbage (Brassica oleracea var. Capitata `Red Drumhead'), and cucumber (Cucumis sativus `Straight Eight'), leaf area and leaf fresh weight in beet (Beta vulgaris `Cylindra' and `Early Wonder'), seedling height and leaf area in spinach (Spinacia oleracea `Long Standing Bloomsdale'), lettuce (Lactuca sativa ``Red Salad Bowl Everest') and `Savoy' cabbage, and seedling height in `Chinese Tip Top' cabbage and lettuce (`Saladin'). `Winterton' cabbage was not affected. UV-B radiation decreased leaf area and leaf fresh weight in common chickweed (Stellaria media) and corn spurry (Spergula arvensis) and seedling height in green foxtail (Setaria viridis) and redroot pigweed (Amaranthus retroflexus). Tillering was stimulated in response to UV-B in green foxtail. There was no effect of UV-B on lady's-thumb (Polygonum persicaria) growth. Leaf number was not affected by exposure to UV-B in any species. The differential morphological sensitivity of vegetable and weed seedlings may result in altered competitive relationships under enhanced UV-B levels expected with the depletion of the earth's ozone layer.

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Differential susceptibility of agricultural weeds to ultraviolet-B radiation

Canadian Journal of Plant Science ◽

10.4141/p01-174 ◽

2002 ◽

Vol 82 (4) ◽

pp. 789-796 ◽

Cited By ~ 18

Author(s):

N. H. Furness ◽

M. K. Upadhyaya

Keyword(s):

Leaf Area ◽

Chenopodium Album ◽

Amaranthus Retroflexus ◽

Ultraviolet B ◽

Setaria Viridis ◽

Stellaria Media ◽

Redroot Pigweed ◽

Green Foxtail ◽

Lamb’S Quarters ◽

Polygonum Persicaria

Differential morphological sensitivity of weed species to ultraviolet-B (UV-B) radiation (290–320 nm) may alter competitive relationships among weeds and associated crop species as the level of this radiation changes. In order to determine relative sensitivity of common chickweed [Stellaria media (L.) Vill.], green foxtail (Setaria viridis L.), lady's-thumb (Polygonum persicaria L.), lamb's-quarters (Chenopodium album L.), redroot pigweed (Amaranthus retroflexus L.), and shepherd's-purse (Capsella bursa-pastoris L.) to this radiation, seedlings were grown under 0, 7, and 11 kJ m-2 d-1 of biologically effective UV-B radiation in a greenhouse for 6 wk. The influence of UV-B radiation on seedling growth and morphology was investigated. UV-B radiation reduced shoot height in green foxtail (by up to 41%), lamb's-quarters, and redroot pigweed, and increased tillering in green foxtail seedlings. Leaf area and leaf biomass in common chickweed, green foxtail, lamb's-quarters, and shepherd's-purse, and stalk biomass in common chickweed, green foxtail, lamb's-quarters, redroot pigweed and shepherd's-purse declined in response to UV-B radiation. In common chickweed, leaf area was reduced by 74% at 11 kJ m-2 d-1. Root biomass was reduced by UV-B radiation in all species (up to 68% at 11 kJ m-2 d-1 in common chickweed) except lady's-thumb. Specific leaf weight increased and leaf area ratio declined in response to UV-B radiation in common chickweed and shepherd's-purse. Exposure to UV-B radiation increased the leaf weight ratio in common chickweed. Shoot:root ratios increased in response to UV-B radiation in common chickweed and redroot pigweed. Scanning electron microscopy revealed collapsed epidermal cells in occasional necrotic regions on adaxial leaf surfaces of redroot pigweed grown under 11 kJ m-2 d-1 UV-B radiation. Morphology and growth of lady's-thumb were not affected by UV-B radiation. This study suggests that common agricultural weeds have differential morphological and growth responses to UV-B-enhanced environments. Sensitivity to UV-B radiation was greatest for common chickweed and least for lady's-thumb and redroot pigweed. Key words: ultraviolet-B, Amaranthus retroflexus, Capsella bursa-pastoris, Chenopodium album, Polygonum persicaria, Setaria viridis, Stellaria media

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A SEASON EXTENSION TECHNIQUE FOR COOL SEASON VEGETABLES USING POLY TUNNELS AND ROW COVERS

HortScience ◽

10.21273/hortsci.28.4.269e ◽

1993 ◽

Vol 28 (4) ◽

pp. 269E-269

Author(s):

Gloria McIntosh ◽

Gerald Klingaman

Keyword(s):

Brassica Oleracea ◽

Brassica Rapa ◽

Spinacia Oleracea ◽

Fresh Weight ◽

Cool Season ◽

Pak Choi ◽

Mild Winter ◽

Row Covers ◽

Additional Protection ◽

Season Extension

Spunbonded polyester or polystyrene row covers were used as additional cold protection for spinach (Spinacia oleracea), kale (Brassica oleracea), pak choi (Brassica rapa) and P-types of lettuce (Lactuca savita) grown in ground beds under unheated polyethylene tunnels during the fall and winter of 1991 and 1992 in climatic zone 6. Temperatures inside poly tunnels averaged 2.4C warmer than outside. Average temperatures were 1.9C warmer than control under polystyrene and 1.5C warmer under spunbonded polyester. Average hourly temperatures showed both row covers offered significantly more cold protection than the greenhouse covering alone; but the two row covers offered similar protection from the cold. Row covers did not result in fresh weight differences in most of the species tested, except kale which had greater fresh weight in control. It may be concluded that during a similar mild winter, these cool season vegetables could be grown under unheated polyethylene tunnels with no additional protection necessary. When temperatures are lower, row covers could provide the protection required to produce these crops.

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Effects of Seeding Density on Growth Attributes of Broadleaf Mustard in Nursery Bed

International Journal of Applied Sciences and Biotechnology ◽

10.3126/ijasbt.v8i1.28257 ◽

2020 ◽

Vol 8 (1) ◽

pp. 65-70

Author(s):

Nisha Niraula ◽

Anil Timilsina

Keyword(s):

Leaf Area ◽

Root Length ◽

Dry Matter ◽

Dry Weight ◽

Seeding Density ◽

Seedling Height ◽

Fresh Weight ◽

Shoot Dry Weight ◽

Broad Leaf ◽

Growth Attributes

The productivity of crops is highly affected by the seedling quality, which is governed by seeding density in the nursery. So, an experiment was conducted to explore the effect of seedling spacing in the growth attributes of Broad Leaf Mustard cv. “Marpha Chauda Paate” at IAAS, Lamjung Campus, during Oct 2018. Four spacing treatments viz 0.5 cm × 1 cm, 1 cm × 1 cm, 1.5 cm ×1.5 cm and 2 cm × 2 cm were arranged in RCB Design with 5 replications. Observation of seedling height, leaf area, leaf number, shoot & root fresh weights, shoot dry matter, and dry matter percentage from twenty-three days old seedlings were recorded. The total leaf area was estimated using the Image-J package. Data were tabulated in MS Excel and analyzed by Gen Stat. Treatments differed significantly in seedling height, shoot and root fresh weight, leaf area, root length, and shoot dry weight, while the number of leaves and dry matter percentage did not differ statistically. Maximum shoot fresh weight (1.09 g), shoot dry weight (0.11 g), leaf area (48.24 cm2), root length (4.89 cm), root fresh weight (0.03 g) per plant and shoot dry matter percentage (9.24%) were found in widest spacing (2 cm × 2 cm). However, seedling height was recorded higher in closer spacing. Therefore, the study of the overall characteristics asserted that the seed spaced at 2 cm × 2 cm produced superior seedling over all other spacings. Int. J. Appl. Sci. Biotechnol. Vol 8(1): 65-70

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Seedling growth and leaf surface morphological responses of three rangeland weeds to ultraviolet-B radiation

Weed Science ◽

10.1017/s0043174500092031 ◽

1999 ◽

Vol 47 (4) ◽

pp. 427-434 ◽

Cited By ~ 9

Author(s):

Nancy H. Furness ◽

Mahesh K. Upadhyaya ◽

Douglas P. Ormrod

Keyword(s):

Leaf Area ◽

Dry Matter ◽

Leaf Surface ◽

Epicuticular Wax ◽

Matter Content ◽

Ultraviolet B ◽

Dry Matter Content ◽

Fresh Weight ◽

Shoot Ratio ◽

Leaf Greenness

The influence of ultraviolet-B (UV-B) radiation on seedling growth and leaf surface characteristics of important rangeland weeds Cynoglossum officinale L. (houndstongue), Centaurea diffusa Lam. (diffuse knapweed), and Tragopogon pratensis L. (meadow salsify) was investigated in a greenhouse by exposing seedlings to 0, 7, or 11 kJ m−2 d−1 of biologically effective UV-B radiation. UV-B radiation reduced leaf, stem, and root fresh weights, leaf area, and leaf: shoot ratio and increased shoot dry matter content, specific leaf weight, and leaf greenness of C. officinale seedlings. Leaf, stem, and root fresh weight, and leaf area of C. diffusa seedlings decreased, whereas shoot dry matter content, specific leaf weight, leaf: shoot ratio, and leaf greenness were unaffected. T. pratensis seedlings exposed to UV-B radiation had diminished leaf greenness, but no change was observed in leaf or stem fresh weight, leaf area, or leaf: shoot ratio. Uniseriate trichome abundance in C. officinale seedlings increased and trichome orientation changed in response to UV-B exposure. UV-B treatments decreased uniseriate trichome abundance in C. diffusa; glandular trichome abundance and the ratio of glandular: uniseriate trichomes were not affected. T. pratensis seedlings showed no change in the amount of epicuticular wax on the adaxial leaf surface in response to UV-B irradiation. Shoot dry weight was not influenced by removal of epicuticular wax prior to UV-B exposure. Results suggest that epicuticular wax is not an important factor in acclimation of T. pratensis seedlings to UV-B radiation. Susceptibility to UV-B–induced damage was greatest for C. officinale seedlings and least for T. pratensis seedlings. Modification of plant morphology or reduction in growth induced by enhanced UV-B radiation may influence competitive relationships between rangeland weeds and their associated forage species.

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Relations Between Growth Parameters in Oil Palm Seedlings Grown in Polybags

Experimental Agriculture ◽

10.1017/s0014479700011029 ◽

1980 ◽

Vol 16 (3) ◽

pp. 275-278 ◽

Cited By ~ 3

Author(s):

E. O. Lucas

Keyword(s):

Leaf Area ◽

Oil Palm ◽

Growth Parameters ◽

Weight Ratio ◽

Dry Weight ◽

Seedling Height ◽

Fresh Weight ◽

Area Index ◽

Non Destructive ◽

Selection Of

SUMMARYThe relation between some growth parameters in polybag oil palm nursery seedlings were assessed. ‘Non-destructive’ parameters such as leaf number, seedling height and girth were highly and positively correlated with one another and with the dry weight of seedlings. Amongst the ‘destructive’ parameters only leaf area, height/weight ratio and fresh weight were positively correlated with dry weight. The Leaf Area Index was poorly correlated with other parameters examined. The relevance of these findings to the selection of oil palm seedlings for transplanting into the field is discussed.

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Floristic composition and relative abundance of weeds in annual crops of Manitoba

Canadian Journal of Plant Science ◽

10.4141/cjps91-117 ◽

1991 ◽

Vol 71 (3) ◽

pp. 831-839 ◽

Cited By ~ 4

Author(s):

A. G. Thomas

Keyword(s):

Relative Abundance ◽

Chenopodium Album ◽

Floristic Composition ◽

Sampling Procedure ◽

Amaranthus Retroflexus ◽

Wild Buckwheat ◽

Wild Oats ◽

Wild Mustard ◽

Green Foxtail ◽

Lamb’S Quarters

Annual surveys for weeds of fields seeded to spring wheat, barley, oats, flax, and canola in Manitoba were conducted during 1978, 1979, and 1981. Fields were surveyed during July and early August each year using a stratified random sampling procedure. Data for the crops and years were combined for analysis. The frequency, the area infested, and the density of the infestation were determined for each species. These three measures of the abundance of the weed were combined into a single synthetic value called relative abundance. Nine of the 152 species recorded by the surveyors accounted for 77% of the total relative abundance. Ranked in order by relative abundance, these species were green foxtail (Setaria viridis (L.) Beauv.), wild oats (Avena fatua L.), wild buckwheat (Polygonum convolvulus L.), annual smartweed (Polygonum spp.), Canada thistle (Cirsium arvense (L.) Scop.), lamb's-quarters (Chenopodium album L.), wild mustard (Sinapis arvensis L.), perennial sow-thistle (Sonchus arvensis L.), and redroot pigweed (Amaranthus retroflexus L.). Green foxtail was the predominant weed with an abundance value three times larger than wild oats or wild buckwheat. The pattern of dominance found in Manitoba fields was similar to results from comparable surveys in Saskatchewan and North Dakota. Key words: Relative abundance, weed survey, weed density, green foxtail, wild oats, wild buckwheat

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Effect of Organic Manures on Growth, Rhizome Yield and Quality Attributes of Turmeric (Curcuma longa L.)

The Agriculturists ◽

10.3329/agric.v10i1.11060 ◽

2012 ◽

Vol 10 (1) ◽

pp. 16-22 ◽

Cited By ~ 2

Author(s):

M. Z. U. Kamal ◽

M. N. Yousuf

Keyword(s):

Leaf Area ◽

Dry Matter ◽

Curcuma Longa ◽

Dry Weight ◽

Fresh Weight ◽

Area Index ◽

Yield Attributes ◽

Organic Manures ◽

Neem Cake ◽

Yield And Quality

The investigation was carried out to evaluate the effect of different organic manures on turmeric with reference to vegetative growth, biomass production, rhizome yield and its attributes of turmeric (Curcuma longa L.). Turmeric showed better response to the application of organic manures. Plant with neem cake application had the taller plant (79.30 cm), maximum number of tillers per plant (5.40), leaf number (5.40), leaf area (44.09) leaf area index (0.429), fresh weight of halum ( 190.05g), fresh weight of root (49.13 g), fresh weight of rhizome per plant (256.21 g) and dry weight of halum (15.21g), dry weight of root (7.32 g), dry weight of rhizome per plant (40.35 g), total dry matter yield (6.85 t ha-1) than those received other types of manures. Moreover, yield attributes such as number of mother rhizomes per plant-1 (1.75), more number of primary rhizomes per plant-1 (5.19), secondary rhizomes per plant-1 (18.03) and tertiary rhizomes per plant (7.69) were also highly accelerated by neem cake application. Similarly, the same treatment expressed the best in terms of size of mother rhizome (7.69 cm), primary rhizome (21.86 cm) and secondary rhizomes (7.05 cm).All these parameters in cumulative contributed to produce the highest estimated fresh rhizomes yield & cured rhizomes yield (29.48 t ha-1, 5.59 t ha-1 respectively). The highest curing percentage (20.28) was observed in T3 treatment having mustard cake@ 2.0 t/ha. Thus, organic manure like neem cake was best fitted natural fertilizer for turmeric cultivation.DOI: http://dx.doi.org/10.3329/agric.v10i1.11060The Agriculturists 2012; 10(1): 16-22

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A method to improve leaf succulence quantification

Brazilian Archives of Biology and Technology ◽

10.1590/s1516-89131999000100002 ◽

1999 ◽

Vol 42 (1) ◽

Cited By ~ 33

Author(s):

André Mantovani

Keyword(s):

Leaf Area ◽

Weight Ratio ◽

Volume Ratio ◽

Dry Weight ◽

Fresh Weight ◽

Ecological Implications ◽

Leaf Succulence ◽

Sun Leaves

Leaf succulence has important physiological and ecological implications. Currently it is quantified by Delf's index (fresh weight/leaf area) and fresh weight/ dry weight ratio. Both indeces are reconsidered and a new index is proposed. Shade and sun leaves from terrestrial, hemiepiphytic and epiphytic aroids were studied. Delf's formula, which does not consider dry weight, overestimated leaf succulence. As fresh weight / dry weight ratio (fw / dw) does not consider leaf area, plants with the same fw / dw ratio were more than five times different in area. The last case was only possible with a decrease in surface / volume ratio and a increase of mesophyll thickness, components not measured by fw / dw ratio. The new index proposed here, which takes into consideration dry weight and leaf area, showed a high correlation to mesophyll thickness.

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PEMANFAATAN PUPUK ORGANIK CAIR PAITAN (Tithonia diversifolia) PADA BERBAGAI DOSIS DAN RAGAM APLIKASINYA TERHADAP PERTUMBUHAN KAILAN (Brassica oleracea Var. Acephala)

JURNAL AGROTEKNOLOGI ◽

10.24014/ja.v11i1.7802 ◽

2020 ◽

Vol 11 (1) ◽

pp. 25

Author(s):

AHMAD TAOFIK ◽

SOFIYA HASANI ◽

AYU CAHYANINGTYAS ◽

BUDY FRASETYA

Keyword(s):

Leaf Area ◽

Plant Height ◽

Analysis Of Variance ◽

Growth Parameters ◽

Organic Fertilizer ◽

Dry Weight ◽

Fresh Weight ◽

Application Method ◽

Randomized Design ◽

Two Factors

The paitan plant contains allelopathic compounds for other plants so that the utilize of paitan plant as a source of liquid organic fertilizer (LOF) has not been widely applied. This research aimed to study the interaction between LOF dosage and appropriate application method of LOF to increase the growth of kailan plants. The research conducted at experimental garden of UIN Bandung from June-August 2016. The experimental design was a completely randomized design with two factors and replicated four times. The first factor was application methods (A), i.e. a1=direct application to the soil, and a2= spraying. The second factor was LOF dosage (T), i.e. t0: 0 ml plant-1, t1: 20 ml plant-1, t2: 40 ml plant-1, t3: 60 ml plant-1, t4: 80 ml plant-1. The growth parameters observed i.e. plant height (14, 21, 28, 35 and 42 Day after Transplanting (DAT)), leaf area 42 DAT, plant dry weight 42 DAT, and plant fresh weight 42 DAT. The data then analyzed with analysis of variance at a significant level of 5%. If the analysis of variance was significant, the Duncan multiple range test was used at α=5%. The research results showed there was no interaction between method of application with a various dosage of paitan LOF to all of the growth parameters. The application paitan LOF showed similar growth in terms of plant height, leaf area, plant dry, and plant fresh weight. The application method of paitan LOF direct to the soil or spraying to leaves can not increase kailan plant growth.

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